My mechanic lent me a beater 1989 300 SEL while my 420 SEL is getting the timing chain bits replaced.

Compared to the 420, the throttle is so jumpy in the 300 SEL that I nearly rear-ended the car in front of me at a traffic light in the first five minutes driving it. The gear changes come at 2,500 or 3,000 rpm in normal driving. Are all the 300s as frantic as this?

These high rpm gear changes are stressing me out.

Its not running right. Our 300E shifts around 1400-1900rpm when mozying through the city, and maybe 2500-2700 when "accelerating briskly". Its not jumpy at all, very smooth and refined.

Somethings wrong with that 300SEL.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

I don't think anything's wrong...the engine revs a little higher on the W126 since it's such a large heavy car with an engine that has a narrow powerband.

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Current cars:
2000 ML55 AMG, 174k miles
2003 C240 T-Modell, 202k miles
1995 S320, 207k Miles

It still shouldn't have a "jumpy" throttle though....it should be smooth. I do agree that it will probably hold out the gears a little longer in the heavy W126....(however, the W126 isn't much heavier than a W124...only by a few hundred lbs....barely an american in the backseat. )

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Probably sits a lot and needs throttle lubrication.

__________________

Gone to the dark side

- Jeff

I had a feeling things were not quite right. There's tons of little stuff wrong with the car.

I'm hoping my next W126 will be a 300 SE(L), so I'm using this opportunity as a test drive.

most likely its a worn out A/T cable frayed or binding . this will change the shift points and jerky .
I am quite content with the smooth shifts in my car .
mak 300se/126